The Qualcast classic petrol 35s is one of the most popular petrol lawnmowers and quite rightly so, it's a really good machine. Now it has two blades, the first is the obvious rotating upper blade but underneath there is also a fixed lower blade, which can often be forgotten about but that does need to be in really good condition to get the best cut. Luckily it’s really easy to replace and that’s what I’m going to show you how to do in this video.

Now, safety first, always make sure your lawnmower is switched off before you do any work. Just to be on the safe side either make sure the throttle is in the ‘stop’ position or disengage the spark plug.

Now to replace the lower blade I don’t need to remove the whole cassette, I just need to tilt the lawnmower onto its back. The blade in held in place by two hex-head screws, so you’ll need a hex head screwdriver or a torx head screwdriver, which will work just as well. I’m using a torx key. So that’s the old blade removed.

Now, if your cassette area is particularly dirty, now is a good time to give it a clean. You can just use warm water and a cloth but you can get dedicated lawnmower cleaning kits such as this one. Now to put the new blade back in place, you just hold it in place, and screw it in.

There you go. With your new lower blade in place you want to check your alignment between the lower blade and the cassette blade, so basically it needs to be the same distance apart along the entire cut. You can do this visually by slowly rotating the blade and checking or you can cut a section of lawn and check that the cut is even. Either way, if you need to adjust the alignment don’t do this by loosening the lower blade, you want to use the adjusting screws on either side of the cassette.

With this done you are all good to go. Lower blades, cassette blades, lawnmower cleaning kits and thousands of parts for Qualcast lawnmowers are available on the eSpares website.